Potential for Metastasis and Recurrence in Colorectal Carcinoma In Situ: A Retrospective Analysis of 1069 Patients.

BACKGROUND: Colorectal carcinoma in situ, characterized by cancer limited to the intramucosal layer or known as intraepithelial carcinoma, has conventionally considered to be without any risk of regional lymph node metastasis. However, isolated cases of regional lymph node metastasis, local recurrence, and distant metastasis challenge this assumption. This study aimed to assess the occurrence of regional lymph node metastasis and recurrence of colorectal carcinoma in situ. METHODS: A retrospective analysis was conducted in 1069 patients who underwent full-thickness local excision or radical surgery for colorectal carcinoma in situ between January 1994 and December 2020. Histopathological features were assessed by 2 experienced pathologists. In cases of suspected recurrence, evaluation involved abdomen-pelvis and chest computed tomography, or PET-CT. RESULTS: The recurrence rate of colorectal carcinoma in situ patients was 0.46%. Among the patients, 9 were diagnosed with regional lymph node metastasis or cancer recurrence. Of these, 4 patients were diagnosed with lymph node metastasis during primary surgery; 2 exhibited regional lymph node metastasis, and 2 presented with both regional and distant lymph node metastases. Regional lymph node metastasis occurred in additional 2 patients after radical surgery for the primary tumor. Distant metastasis was observed in 3 patients: hepatic metastasis in 1, hepatic and pulmonary metastases in another, and small bowel metastasis in the third patient. Among the 5 patients experiencing cancer recurrence, 1 expired due to cancer progression. CONCLUSION: Contrary to previous assumptions, colorectal carcinoma in situ can potentially metastasize to lymph nodes and recur. Therefore, careful assessment at the time of diagnosis is crucial, recognizing the possibility of lymph node metastasis or recurrence. This approach is essential for accurately identifying instances of cancer recurrence and ensuring optimal oncological outcomes.

Predicting survival in locally advanced rectal cancer with effective chemoradiotherapy response.

BACKGROUND: Locally advanced rectal cancer patients often display favorable responses and favorable oncologic outcomes. Due to the low recurrence rate, there is scarcity of studies investigating the prognostic factors influencing their survival. Therefore, our study sought to assess the prognostic factors associated with survival in rectal cancer patients who achieved either a pathologic complete response or a pathologic stage I after neoadjuvant chemoradiotherapy combined with radical resection. METHODS: In this retrospective study, we analyzed data from cohort of 1394 patients diagnosed with locally advanced rectal cancer who underwent neoadjuvant chemoradiotherapy combined with total mesorectal excision from January 2008 to April 2017. Finally, we selected 474 (34.2 %) who exhibited either a pathologic complete response or attained pathologic stage I following the treatment. Subsequently, we analyzed the prognostic factors influencing disease-free and overall survival. RESULTS: A total of 161 (34 %) achieved a pathologic complete response. Our analysis revealed that circumferential resection margin and the administration of adjuvant chemotherapy were prognostic factors for disease-free survival (p = 0.011, p = 0.022). Furthermore, factors influencing overall survival included the clinical N stage and administration of adjuvant chemotherapy (p = 0.035, p = 0.015). CONCLUSION: In conclusion, the circumferential resection margin, clinical N stage, and administration of adjuvant chemotherapy were prognostic factors for survival in patients showing good response to neoadjuvant chemoradiotherapy in locally advanced rectal cancer. For patients with a positive circumferential resection margin and clinical N (+) stage, intensive follow-up might be needed to achieve favorable oncologic outcomes. Also, we recommend considering adjuvant chemotherapy as a beneficial treatment approach for these patients.

Pulmonary Metastasis as the First Site of Metastasis After Curative Surgery for Colon Cancer: Incidence and Risk Factors According to the TNM Stage.

BACKGROUND: The lungs are one of the most common sites for colon cancer metastasis. A few studies reported that approximately 2% to 10% of patients with colon cancer developed pulmonary metastasis. However, among these studies, patient characteristics were heterogeneous, and information on pulmonary metastasis incidence by the TNM stage was scarce. OBJECTIVE: This study evaluated the incidence of pulmonary metastasis in colon cancer without synchronous metastasis treated with radical surgery and identified risk factors for pulmonary metastasis according to the TNM stage. DESIGN AND SETTINGS: This retrospective study included all patients with colon cancer without metastasis who underwent radical surgery for primary tumor at Samsung Medical Center between January 2007 and December 2016. PATIENTS: A total of 4889 patients who underwent radical surgery for stage I and III colon cancer were included. MAIN OUTCOME MEASURES: The main outcome measures were the incidence of pulmonary metastasis and overall survival. RESULTS: A total of 156 patients (3.2%) were diagnosed with pulmonary metastasis after a median of 16 months from the time of radical surgery for colon cancer to detection of pulmonary metastasis. The pulmonary metastasis incidence rate by the TNM stage was 0.5% in stage I, 1.6% in stage II, and 6% in stage III. Risk factors for pulmonary metastasis were preoperative CEA >5 ng/mL, cancer obstruction, N stage, vascular invasion, perineural invasion, and adjuvant chemotherapy for primary colon cancer in multivariable analysis. LIMITATION: This was a retrospective single-center study. CONCLUSIONS: Preoperative CEA >5 ng/mL, cancer obstruction, pN stage, vascular invasion, perineural invasion, and receiving adjuvant chemotherapy for primary colon cancer were risk factors for pulmonary metastasis in colon cancer. Therefore, patients with risk factors for pulmonary metastasis should be recommended for intensive follow-up to detect lung metastases. See Video Abstract . METSTASIS PULMONAR EN EL PRIMER SITIO TRAS CIRUGA CURATIVA DEL CNCER DE COLON INCIDENCIA Y FACTORES DE RIESGO SEGN ESTADIO TNM: ANTECEDENTES:Los pulmones son uno de los sitios más comunes de metástasis del cáncer de colon. Algunos estudios informaron que aproximadamente entre el 2% y el 10% de los pacientes con cáncer de colon desarrollaron metástasis pulmonar. Sin embargo, entre estos estudios, las características de los pacientes fueron heterogéneas y la información sobre la incidencia de metástasis pulmonares según el estadio TNM fue escasa.OBJETIVO:Este estudio evaluó la incidencia de metástasis pulmonar en cáncer de colon sin metástasis sincrónica tratada con cirugía radical e identificó factores de riesgo para metástasis pulmonar según el estadio TNM.DISEÑO Y AJUSTES:Este estudio retrospectivo incluyó a todos los pacientes con cáncer de colon sin metástasis que se sometieron a cirugía radical por tumor primario en el Samsung Medical Center entre enero de 2007 y diciembre de 2016.PACIENTES:Se incluyó un total de 4.889 pacientes sometidos a cirugía radical por cáncer de colon en estadio I-III.PRINCIPALES MEDIDAS DE RESULTADO:Las principales medidas de resultado fueron la incidencia de metástasis pulmonar y la supervivencia general.RESULTADOS:Un total de 156 pacientes (3,2%) fueron diagnosticados con metástasis pulmonar con una duración media de 16 meses desde el momento de la cirugía radical por cáncer de colon hasta la detección de la metástasis pulmonar. La tasa de incidencia de metástasis pulmonares por estadio TNM fue del 0,5% en el estadio I, del 1,6% en el estadio II y del 6% en el estadio III. Los factores de riesgo de metástasis pulmonar fueron CEA preoperatorio superior a 5 ng/ml, obstrucción por cáncer, estadio N, invasión vascular, invasión perineural y quimioterapia adyuvante para el cáncer de colon primario en un análisis multivariable.LIMITACIÓN:Este fue un estudio retrospectivo de un solo centro.CONCLUSIÓN:CEA preoperatorio superior a 5 ng/ml, obstrucción por cáncer, estadio pN, invasión vascular, invasión perineural y recibir quimioterapia adyuvante para el cáncer de colon primario fueron factores de riesgo de metástasis pulmonar en el cáncer de colon. Por lo tanto, se debe recomendar un seguimiento intensivo a los pacientes con factores de riesgo de metástasis pulmonares para detectar metástasis pulmonares. (Traducción-Dr Yolanda Colorado ).

Are curiosity and situational interest different? Exploring distinct antecedents and consequences.

BACKGROUND: A controversy over the distinction between curiosity and situational interest has recently resurfaced. Nonetheless, empirical research comparing the two is noticeably lacking. AIMS: We attempted to fill this gap and provide much-needed evidence of the distinction between curiosity and situational interest by examining the antecedents and consequences of the two constructs. METHODS: We assessed enjoyment, novelty, uncertainty and surprise as potential antecedents and information seeking, individual interest, career intention and achievement as potential outcomes of curiosity and situational interest among 219 Korean sixth graders in the domain of science. RESULTS: Of the hypothesized antecedents, enjoyment during science class related most strongly to students' situational interest in science, whereas novelty in science class related most strongly to students' science curiosity. Uncertainty and surprise in science class related to only science curiosity and not situational interest in science. Among the outcomes considered, situational interest in science related to only students' individual interest in science. In comparison, science curiosity related significantly to all science outcomes measured in this study. Science curiosity also significantly mediated the relationships between the antecedents and outcomes in science. CONCLUSIONS: Together, these results support the distinction between curiosity and situational interest and suggest different ways to promote each motivation construct depending on desired outcomes in the science classroom.

The Prognostic Value of Micropapillary Pattern in Colon Cancer and Its Role as a High-Risk Feature in Patients With Stage II Disease.

BACKGROUND: The association of a micropapillary pattern with oncologic outcomes has not been fully studied in patients with colon cancer. OBJECTIVE: We evaluated the prognostic value of a micropapillary pattern, especially for patients with stage II colon cancer. DESIGN: A retrospective comparative cohort study using propensity score matching. SETTING: This study was conducted at a single tertiary center. PATIENTS: Patients with primary colon cancer undergoing curative resection from October 2013 to December 2017 were enrolled. Patients were grouped into micropapillary pattern positive or micropapillary pattern negative. MAIN OUTCOME MEASUREMENTS: Disease-free survival and overall survival. RESULTS: Of the eligible 2192 patients, 334 (15.2%) were with micropapillary pattern (+). After 1:2 propensity score matching, 668 patients with micropapillary pattern-negative status were selected. The micropapillary pattern-positive group showed significantly worse 3-year disease-free survival (77.6% vs 85.1%, p = 0.007). Three-year overall survival of micropapillary pattern-positive and micropapillary pattern-negative patients did not show a statistically significant difference (88.9% vs 90.4%, p = 0.480). In multivariable analysis, micropapillary pattern-positive was an independent risk factor for poor disease-free survival (HR 1.547, p = 0.008). In the subgroup analysis for 828 patients with stage II disease, 3-year disease-free survival deteriorated significantly in micropapillary pattern-positive patients (82.6% vs 93.0, p < 0.001). Three-year overall survival was 90.1% and 93.9% in patients positive and negative for micropapillary pattern, respectively ( p = 0.082). In the multivariable analysis for patients with stage II disease, micropapillary pattern-positive status was an independent risk factor for poor disease-free survival (HR 2.003, p = 0.031). LIMITATIONS: Selection bias due to the retrospective nature of the study. CONCLUSIONS: Micropapillary pattern-positive status may serve as an independent prognostic factor for colon cancer, especially for patients with stage II disease. VALOR PRONSTICO DEL PATRN MICROPAPILAR Y SU PAPEL COMO CARACTERSTICA DE ALTO RIESGO EN PACIENTES CON CNCER DE COLON EN ESTADO II: ANTECEDENTES:La asociación del patrón micropapilar con los resultados oncológicos no ha sido completamente estudiada en pacientes con cáncer de colon.OBJETIVO:Evaluamos el valor pronóstico del patrón micropapilar, especialmente en pacientes con cáncer de colon en estadio II.DISEÑO:Estudio de cohortes comparativo y retrospectivo que utilize el emparejamiento por puntuación de propensiones.AJUSTE:Estudio realizado en un solo centro terciario.PACIENTES:Se incluyeron los pacientes con cáncer de colon primario sometidos a resección curativa desde octubre de 2013 hasta diciembre de 2017. Los pacientes se agruparon en patrón micropapilar positivo ( + ) o patrón micropapilar negativo ( - ).PRINCIPALES MEDIDAS DE RESULTADO:Sobrevida libre de enfermedad y la sobrevida global.RESULTADOS:De los 2192 pacientes elegibles, 334 (15,2%) tenían patrón micropapilar (+). Después de emparejar el puntaje de propensión 1:2, se seleccionaron 668 pacientes con patrón micropapilar (-). El grupo con patrón micropapilar (+) mostró una sobrevida libre de enfermedad significativamente inferior a los tres años (77,6% frente a 85,1%, p = 0,007). La sobrevida global a los tres años del patrón micropapilar (+) y del patrón micropapilar (-) no mostró una diferencia estadísticamente significativa (88,9 % frente a 90,4%, p = 0,480). En el análisis multivariable, el patrón micropapilar (+) fue un factor de riesgo independiente para una deficiente sobrevida libre de enfermedad (índice de riesgo 1,547, p = 0,008). En el análisis de subgrupos de 828 pacientes con enfermedad en estadio II, la sobrevida libre de enfermedad a los tres años se deterioró significativamente en los pacientes con patrón micropapilar (+) (82,6% frente a 93,0, p < 0,001). La sobrevida global a los tres años fué del 90,1% y del 93,9% en el patrón micropapilar (+) y el patrón micropapilar (-), respectivamente ( p = 0,082). En el análisis multivariable de los pacientes con enfermedad en estadio II, el patrón micropapilar (+) fue un factor de riesgo independiente para una sobrevida libre de enfermedad deficiente (índice de riesgo 2,003, p = 0,031).LIMITACIONES:Sesgo de selección debido a la naturaleza retrospectiva del estudio.CONCLUSIONES:El patrón micropapilar (+) sirve como factor pronóstico independiente para el cáncer de colon, especialmente para pacientes con enfermedad en estadio II. (Traducción-Dr. Xavier Delgadillo ).

Prognostic Impact of Mucinous Adenocarcinoma in Stage II and III Colon Cancer.

BACKGROUND: Mucinous adenocarcinoma is a rare histologic feature of colorectal cancer and is characterized by oncologic features that are different from those of adenocarcinoma. However, there are conflicting views regarding the prognostic impact of mucinous adenocarcinoma on colon cancer. OBJECTIVE: This study aimed to evaluate the prognostic impact of mucinous adenocarcinoma in stage II and III colon cancer. DESIGN: This was a retrospective cohort study. SETTINGS: This study was conducted between January 2010 and December 2015. Patients were divided into the mucinous adenocarcinoma and nonmucinous adenocarcinoma groups. Disease-free survival and overall survival were assessed using propensity score matching. PATIENTS: Overall, 2532 patients who underwent radical surgery for stage II and III colon cancer were included in the study. MAIN OUTCOME MEASURES: The main outcome measures were disease-free survival and overall survival. RESULTS: The median follow-up duration was 86 months. The disease-free survival and overall survival were significantly lower in the mucinous adenocarcinoma group than in the nonmucinous adenocarcinoma group. In subgroup analysis, there was no significant difference in the disease-free survival and overall survival between patients with and without mucinous adenocarcinoma with stage II colon cancer. In stage III colon cancer, the disease-free survival and overall survival were significantly lower in patients with mucinous adenocarcinoma than in those without mucinous adenocarcinoma. Multivariable analysis showed that mucinous adenocarcinoma was a poor prognostic factor for disease-free survival and overall survival. LIMITATION: The study's limitations include those that are inherently associated with retrospective single-center studies. CONCLUSIONS: Mucinous adenocarcinoma is a poor prognostic factor in stage III but not in stage II colon cancer. Therefore, mucinous adenocarcinoma might not be regarded as an independent risk factor requiring chemotherapy for favorable oncologic outcomes. However, for stage III colon cancer, patients with mucinous adenocarcinoma require close observation. IMPACTO PRONSTICO DEL ADENOCARCINOMA MUCINOSO EN LAS ETAPAS II Y III DE CNCER DE CLON: ANTECEDENTES:El adenocarcinoma mucinoso es una característica histológica rara del cáncer colorrectal, se caracteriza por propiedades oncológicas que son diferentes a las del adenocarcinoma. Sin embargo, existen puntos de vista contradictorios con respecto al impacto pronóstico del adenocarcinoma mucinoso en el cáncer de colon.OBJETIVO:Este estudio tuvo como objetivo evaluar el impacto pronóstico del adenocarcinoma mucinoso en las etapas II y III de cáncer de cólon.DISEÑO Y CONFIGURACIONES:Este estudio de cohorte retrospectivo se realizó entre enero de 2010 y diciembre de 2015. Los pacientes se dividieron entre grupos de adenocarcinoma mucinoso y adenocarcinoma no mucinoso. La supervivencia libre de enfermedad y la supervivencia global se evaluaron utilizando emparejamiento por puntuación de propensión.PACIENTES:En general, 2,532 pacientes que se sometieron a cirugía radical para etapa II y III de cáncer de colon se incluyeron en el estudio.PRINCIPALES MEDIDAS DE RESULTADO:Las principales medidas de resultado fueron la supervivencia libre de enfermedad y la supervivencia general.RESULTADOS:La mediana de duración del seguimiento fue de 86 meses. La supervivencia libre de enfermedad y la supervivencia global fueron significativamente menores en el grupo de adenocarcinoma mucinoso que en el grupo de adenocarcinoma no mucinoso. En el análisis de subgrupos, no hubo diferencias significativas en la supervivencia libre de enfermedad y la supervivencia global entre los pacientes con o sin adenocarcinoma mucinoso con cáncer de cólon etapa II. En el cáncer de colon etapa III, la supervivencia libre de enfermedad y la supervivencia global fueron significativamente más bajas en pacientes con adenocarcinoma mucinoso que en aquellos sin adenocarcinoma mucinoso. El análisis multivariable mostró que el adenocarcinoma mucinoso era un factor de mal pronóstico para la supervivencia libre de enfermedad y la supervivencia global.LIMITACIONES:Las limitaciones del estudio incluyen aquellas que están inherentemente asociadas con estudios retrospectivos de un solo centro.CONCLUSIONES:El adenocarcinoma mucinoso es un factor de mal pronóstico en el cáncer de colon etapa III pero no en etapa II. Por lo tanto, el adenocarcinoma mucinoso podría no considerarse un factor de riesgo independiente que requiera quimioterapia para obtener resultados oncológicos favorables. Sin embargo, para el cáncer de colon etapa III, los pacientes con adenocarcinoma mucinoso requieren observación cercana. (Traducción-Dr. Aurian Garcia Gonzalez ).

A Phase II Study of Preoperative Chemoradiotherapy with Capecitabine Plus Simvastatin in Patients with Locally Advanced Rectal Cancer.

PURPOSE: The purpose of this phase II trial was to evaluate whether the addition of simvastatin, a synthetic 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitor, to preoperative chemoradiotherapy (CRT) with capecitabine confers a clinical benefit to patients with locally advanced rectal cancer (LARC). MATERIALS AND METHODS: Patients with LARC (defined by clinical stage T3/4 and/or lymph node positivity) received preoperative radiation (45-50.4 Gy in 25-28 daily fractions) with concomitant capecitabine (825 mg/m2 twice per day) and simvastatin (80 mg, daily). Curative surgery was planned 4-8 weeks after completion of the CRT regimen. The primary endpoint was pathologic complete response (pCR). The secondary endpoints included sphincter-sparing surgery, R0 resection, disease-free survival, overall survival, the pattern of failure, and toxicity. RESULTS: Between October 2014 and July 2017, 61 patients were enrolled; 53 patients completed CRT regimen and underwent total mesorectal excision. The pCR rate was 18.9% (n=10) by per-protocol analysis. Sphincter-sparing surgery was performed in 51 patients (96.2%). R0 resection was achieved in 51 patients (96.2%). One patient experienced grade 3 liver enzyme elevation. No patient experienced additional toxicity caused by simvastatin. CONCLUSION: The combination of 80 mg simvastatin with CRT and capecitabine did not improve pCR in patients with LARC, although it did not increase toxicity.

The role of transanal tube after low anterior resection in patients with rectal cancer treated with neoadjuvant chemoradiotherapy: A propensity score-matched study.

BACKGROUND: The protective efficacy of transanal tube for anastomosis was compared with that of diverting stoma in patients with rectal cancer treated with neoadjuvant chemoradiotherapy. METHODS: We included consecutive patients with rectal cancer treated with neoadjuvant chemoradiotherapy and curative surgery from January 2013 to December 2019. The patients were grouped into transanal tube or diverting stoma, according to the protection methods they received. Propensity score-matching with 1:1 ratio was done. The primary outcome was the incidence of anastomotic leakage. RESULTS: Of the 656 eligible patients, 207 (31.6%) and 385 (58.7%) patients were grouped into transanal tube and diverting stoma, respectively, and 64 (9.7%) patients who did not undergo either transanal tube or diverting stoma were excluded. After matching, the incidence of anastomotic leakage was 9.7% and 10.6% in diverting stoma and transanal tube, respectively (P = .871). The overall morbidity was 23.2% and 15.0% in diverting stoma and transanal tube, respectively (P = .045). In the multivariate analysis, tumor size >2.5 cm and level of anastomosis <4 cm were significant risk factors for anastomotic leakage. In a subgroup analysis for patients with the level of anastomosis >4 cm, the incidence of anastomotic leakage was not significantly different between the transanal tube and diverting stoma groups. However, for patients with a level of anastomosis <4 cm, the incidence of grade C anastomotic leakage was significantly greater in the transanal tube than in the diverting stoma group (2.5% vs 9.9%, P = .040). CONCLUSION: The protective efficacy of transanal tube may be comparable to diverting stoma, especially for those with a level of anastomosis >4 cm.

Bevacizumab increases the risk of anastomosis site leakage in metastatic colorectal cancer.

Background: Bevacizumab is a humanized monoclonal antibody against vascular endothelial growth factor and is used in combination with first-line chemotherapy in the treatment of metastatic colorectal cancer. One of the side effects of bevacizumab is gastrointestinal perforation. This study was designed to identify the effect of bevacizumab in intestinal anastomosis site healing. Methods: From January 2010 to December 2020, patients diagnosed with stage IV colorectal cancer treated with palliative chemotherapy or chemoradiotherapy followed by radical surgery were retrospectively reviewed. Clinical signs or symptoms and computed tomography were tools used for diagnosing anastomosis site leakage. The patients were divided into two groups, the bevacizumab group (n = 136) and the non-bevacizumab group (n = 124). Results: Among the 260 patients 14 (5.4%) patients were diagnosed with anastomosis site leakage. In the bevacizumab group, 13 (9.6%) patients were diagnosed with anastomotic leakage. In the non-bevacizumab group, 1 (0.8%) patient was diagnosed with anastomotic leakage. Anastomosis site leakage was significantly higher in the bevacizumab treatment group (P < 0.001). In the bevacizumab group, period of drug discontinuation before surgery was factor associated with anastomosis site leakage in multivariable analysis (P = 0.031). Conclusion: Stage IV colorectal patients treated with bevacizumab before radical surgery for primary cancer should be carefully observed of anastomosis site leakage after surgery, and the period of drug discontinuation before surgery should be longer than 5 weeks to avoid anastomosis site leakage.

Correlation between T stage and lymph node metastasis in rectal cancer treated with preoperative chemoradiotherapy.

Background: Depth of tumor is a risk factor for lymph node metastasis in rectal cancer, but impact of yield pathologic T (ypT) stage on lymph node involvement in rectal cancer remains unclear. The aim of this study was to evaluate the correlation between ypT stage and lymph node metastasis. Methods: From January 2010 to December 2015, 602 patients who were diagnosed with rectal cancer and treated with neoadjuvant chemoradiotherapy (CRT) followed by radical operation were reviewed retrospectively. The correlations between ypT stage and lymph node status and survival were evaluated. Results: On pathology, 179 (29.7%) patients exhibited regional lymph node metastasis. Lymph node metastasis was seen in 8.5% of ypT0 patients, 20% of ypT1, 18.4% of ypT2, 47.5% of ypT3, and 27.3% of ypT4. Positive lymph node metastasis was correlated with ypT stage. In addition, the difference of lymph node metastasis in ypT stage subgroups was statistically significant (p < 0.001). Five-year disease-free survival was significantly different in the ypT stage subgroups (88.7% versus 86.7% versus 82.6% versus 64.7% versus 72.7%, p < 0.001), as was 5-year overall survival (96.2% versus 90.0% versus 95.8% versus 80.0% versus 90.9%, p < 0.001). Conclusion: YpT stage is associated with lymph node metastasis in rectal cancer treated with neoadjuvant CRT and radical operation, and ypT0 patients exhibited an 8.5% lymph node metastasis rate. Therefore, the decision for local excision or the watch-and-wait strategy for rectal cancer treated with neoadjuvant CRT and predicted to show a pathologic complete response should be considered with caution.

Regional Metabolic Changes Influencing Three-Dimensional Perception in Parkinson's Disease.

BACKGROUND AND PURPOSE: Stereopsis refers to the perception of depth and awareness of the distance of an object from the observer that results from the brain receiving visual stimuli from both eyes in combination. Patients with idiopathic Parkinson's disease (PD patients) typically experience problems with vision, eyeball movements, and visual perception due to degeneration of the cells that generate dopamine in the brain. We therefore hypothesized that stereopsis is affected more by visual cortical dysfunction in idiopathic PD than by retina and subcortical structural dysfunction. METHODS: We analyzed stereopsis in 12 PD patients and 7 healthy controls using a three-dimensional (3D) television (TV). Before allowing patients to watch TV, we examined their visual acuity and strabismus using the Titmus Stereo Fly Test, and evaluated their cognitive function using cognitive tests. The patients watched 3D and two-dimensional (2D) versions of a movie with an approximate duration of 17 minutes, and then completed a questionnaire about stereopsis. All subjects underwent brain F-18 fluorodeoxyglucose (FDG) positron-emission tomography after watching the 3D version of the movie. One week later, subjects watched the 2D version of the same movie under the same conditions. Each scan was analyzed using statistical parametric mapping (version 8) software. RESULTS: The visual cortex was activated less in the PD patients than in the healthy controls when watching the 2D or 3D movie. However, there was no significant difference between watching 2D and 3D movies in the PD patients or healthy controls. CONCLUSIONS: The lower activation of the primary visual cortex in PD patients suggests the presence of dysfunction of the visual cortex. In addition, there was less activation of the visual association cortex in PD patients when watching a 3D movie than in controls under the same conditions. This might be one reason why PD patients do not recognize real and dynamic stereopsis. These findings have clinical significance since they suggest that safety needs to be considered when making devices or programs using 3D or virtual reality for use by patients with various cerebral degenerative diseases.

Posterior Type of Alzheimer's Dementia Presenting with Homonymous Hemianopsia.

BACKGROUND: Alzheimer's disease is a chronic neurodegenerative condition, mostly affecting the medial temporal lobe and associated neocortical structures. In this report, we present a rare clinical manifestation of this disease. CASE REPORT: A 61-year-old female with word finding difficulty and memory disturbances was diagnosed with Alzheimer's disease. Two years later, she complained of right homonymous hemianopia without optic ataxia, ocular apraxia, and simultagnosia. No findings other than parenchymal disease were apparent in magnetic resonance imaging and laboratory tests. CONCLUSIONS: In this case, in a patient initially diagnosed with Alzheimer's dementia with progressive disease, we found only homonymous hemianopia, without signs of Balint's syndrome or Gerstmann's syndrome. After careful investigation showing that Alzheimer's dementia with visual symptom was not associated with parenchymal disease, we concluded a case of atypical variant of Alzheimer's disease.

Robotic transverse colectomy for mid-transverse colon cancer: surgical techniques and oncologic outcomes.

Robot-assisted surgery for colon cancer has been reported in many studies, most of which worked on right and/or sigmoid colectomy. The aim of this study was to report our experience of robotic transverse colectomy with an intracorporeal anastomosis, provide details of the surgical technique, and present the theoretical benefits of the procedure. This is a retrospective review of prospectively collected data of robotic surgery for colorectal cancer performed by a single surgeon between May 2007 and February 2011. Out of 162 consecutive cases, we identified three robotic transverse colectomies, using a hand-sewn intracorporeal anastomosis. Two males and one female underwent transverse colectomies for malignant or premalignant disease. The mean docking time, time spent using the robot, and total operative time were 5, 268, and 307 min, respectively. There were no conversions to open or conventional laparoscopic technique. The mean length of specimen and number of lymph nodes retrieved were 14.1 cm and 6.7, respectively. One patient suffered from a wound seroma and recovered with conservative management. The mean hospital stay was 8.7 days. After a median follow-up of 72 months, there were no local or systemic recurrences. Robotic transverse colectomy seems to be a safe and feasible technique. It may minimize the necessity of mobilizing both colonic flexures, with facilitated intracorporeal hand-sewn anastomosis. However, further prospective studies with a larger number of patients are required to draw firm conclusions.

Learning curves for single incision and conventional laparoscopic right hemicolectomy: a multidimensional analysis.

PURPOSE: This study aimed to compare the learning curves and early postoperative outcomes for conventional laparoscopic (CL) and single incision laparoscopic (SIL) right hemicolectomy (RHC). METHODS: This retrospective study included the initial 35 cases in each group. Learning curves were evaluated by the moving average of operative time, mean operative time of every five consecutive cases, and cumulative sum (CUSUM) analysis. The learning phase was considered overcome when the moving average of operative times reached a plateau, and when the mean operative time of every five consecutive cases reached a low point and subsequently did not vary by more than 30 minutes. RESULTS: Six patients with missing data in the CL RHC group were excluded from the analyses. According to the mean operative time of every five consecutive cases, learning phase of SIL and CL RHC was completed between 26 and 30 cases, and 16 and 20 cases, respectively. Moving average analysis revealed that approximately 31 (SIL) and 25 (CL) cases were needed to complete the learning phase, respectively. CUSUM analysis demonstrated that 10 (SIL) and two (CL) cases were required to reach a steady state of complication-free performance, respectively. Postoperative complications rate was higher in SIL than in CL group, but the difference was not statistically significant (17.1% vs. 3.4%). CONCLUSION: The learning phase of SIL RHC is longer than that of CL RHC. Early oncological outcomes of both techniques were comparable. However, SIL RHC had a statistically insignificant higher complication rate than CL RHC during the learning phase.

Risk factors for the requirement of surgical or endoscopic interventions during chemotherapy in patients with uncomplicated colorectal cancer and unresectable synchronous metastases.

BACKGROUND AND OBJECTIVES: The purpose of this study was to determine the risk factors for requirement of surgical or endoscopic interventions for complications caused by the primary tumor during chemotherapy in patients with unresectable metastatic colorectal cancer. METHODS: A total of 259 patients were diagnosed with uncomplicated colorectal cancer with unresectable metastatic disease and underwent chemotherapy as an initial treatment. Among them, 57 (22.0%) patients underwent palliative interventions because of complications caused by the primary tumor during chemotherapy, including bypass surgery or diverting enterostomy for 22 patients, insertion of colonic stent for 22, and resection of primary tumor for 13. RESULTS: Multivariate analysis revealed that rectal lesion (RR, 2.132; 95% CI, 1.080-4.210; P = 0.029) and tumor size larger than 5 cm (RR = 3.644, 95% CI = 1.923-6.902; P < 0.001) were significant risk factors for requirement of palliative intervention. Patients who had none of the risk factors showed better overall survival than those who had one or more (P = 0.021). CONCLUSIONS: Tumor location in rectum and tumor size larger than 5 cm were significant risk factors for the requirement of surgical or endoscopic interventions during chemotherapy for complications caused by the primary tumor in patients with unresectable metastatic colorectal cancer.

Preoperative three-dimensional CT angiography to distinguish between an aberrant subclavian artery and a double aortic arch in thyroid surgery: Report of 2 cases.

A non-recurrent inferior laryngeal nerve (NRILN), a very rare anatomic variation, is easily damaged during thyroid surgery. Due to impairments during embryonic development, a NRILN is frequently associated with an aberrant subclavian artery. Thus, an aberrant subclavian artery is now regarded as an important vascular anomaly for predicting the presence of a NRILN using various imaging modalities. However, precise imaging is often necessary as other vascular anomalies, such as a double aortic arch, can cause difficulties in discriminating between an aberrant subclavian artery and other anatomic variations. For this reason, computed tomography (CT) is usually necessary before thyroid surgery. but, to take more precise images, newly developed techniques such as computed tomography angiography (CTA) are needed. To indentify NRILNs, we performed CTA preoperatively in two patients with thyroid cancer. CTA demonstrated an aberrant subclavian artery with an associated NRILN in one patient and a double aortic arch with a recurrent inferior laryngeal nerve (RILN) in the second patient. Thyroid surgery was successful, and the laryngeal nerve was preserved in both patients. Preoperative CTA is much safer and less time-consuming than catheter angiography. Also, CTA is a cost-effective three-dimensional imaging modality for identifying aberrant subclavian arteries associated with NRILNs, as compared with double aortic arches associated with RILNs.

Sphincter-preserving operations without defunctioning stoma.

Sphincter-preserving operations have increasingly been carried out during the last few decades; nevertheless, temporary defunctioning stoma is still being frequently used for low colorectal anastomosis (LCRA) with staplers and hand-sewn coloanal anastomosis (CAA). From 1994 to 2003, 131 consecutive patients with rectal cancer with tumours within 7 cm from the anal verge underwent LCRA or CAA without defunctioning stoma. Anastomotic complications and treatment were compared between the groups. The median follow up was 31.4 months. Complications related to anastomosis were 10.7% for LCRA with 7.1% of anastomotic leakage (two men and two women) and 13.3% for CAA with 4.0% of anastomotic leakage (three men). Treatments for leakage included colostomy (three LCRA), CAA construction (one LCRA) and conservative treatment (three CAA). Twenty eight percent of CAA received preoperative radiation therapy, and the anastomic leakage developed in 14% of them. Anastomotic leakage and its treatment with CAA are different from those in LCRA, and CAA can safely be used without defunctioning stoma during sphincter-preserving operation for low-lying rectal cancer.